DIFFERENCE CRDI VS MPFI

1. MPFi V/S CRDi
V/S

2. MPFI : mean multi point fuel injection system ie. in
petrol engine for gaining more uniform Air Fuel
blending fuel is injected at various point in the path of
air. this tech is used in light weight car running on
petrol. there is also milage improvement due to this.
but in case of DTSI(digital twin spark ignition) : the
engine cylinder consist of two no of spark plug for
proper combustion of charge.

3. DTSI : It is the DIGITAL TWIN SPARK IGNITION system.
The principle of operation is that, there is an additional SPARK
PLUG introduced at the other end of the combustion chamber
along with the usual spark plug with the the traditional
placement at the top centre.
The idea was introduced considering the SLOWER Flame
Propogation with only one Spark Plug as in traditional engine
design.
Also due to the rectangular shape of the Combustion Chamber
the Flame could not reach all the sides and corners regions of
the Combustion Chamber, thus leaving some amount of the
A/F mixture UNBURNT.

4. Both the above points were a drawback resulting in :
Slower and Incomplete burnig of the A/F mixture thus Producing
LESSER POWER, LOWER FUEL EFFICIENCY and HIGHER HC
EMISSIONS.
By introducing the DTSI, due to Two Spark Plugs at two opposite ends
of the Combustion chamber, there is:
Faster and More Precise Flame Propogation and,
Better reach of the Flame covering more chamber space resulting in
Greater amount of mixture burned in a more even manner.
There is also Swirl Induction incorporated at times for bettermixing
inside the combustion Chamber and give better Burning of the fuel.
Both these Improvisations lead to Higher Fuel Efficiency and Higher
Power and Torque Developed.
This considerably Improves the Engine Performance, than
the traditional FI systems.

5. The Engine Power and Torque is believed to improve by nearly 8%
by using DTSI
Also the DTSI is combined with the COMPUTERISED DIRECT
IGNITION or CDI which is an eight bit microprocessor chip with
preprogrammed maps of Ignition Timings for various engine rpms
and engine loads.
The CDI works along with the THROTTLE RESPONSIVE IGNITION
CONTROL SYSTEM. This TRICS controls the Ignition based upon
the Amount of Throttle Opening.
Thus when the rider Accelerates suddenly or goes on a smooth
uniform drive mode, the Ignition requirement varies acccordingly
Hence the Throttle openig also changes, this is sensed by the
TRICS which accordingly opens and closes the Reed Switch
operated magnetically. This TRICS is connected to the CDI which
inturn controls the IGNITION SPARK ADVANCE AND TIMING thus
giving a much efficient SPARK ADVANCE for every engine rpm and
load conditions.
This eventually increases the Engine Performance and Fuel
Efficiency of the vehicle and reduces the HC Emissions.

6. MPFI : It is the MULTIPORT FUEL IGNITION system.
In this there is at least ONE INDIVIDUAL FUEL INJECTION
NOZZLE/PORT for EVERY INDIVIDUAL CYLINDER of the Engine as
opposed to the ONE CENTRAL FUEL PORT in the traditional Engine
design.
The basic idea is to provide better ratio of A/F mixture in every cylinder
nearing the Stoichiometric Value of 14.7 : 1 as far as possible for all
various speeds (rpm) and acceleration demands. This was not so much
achievable with the single central fuel port system.
This system allows to have a desired A/F ratio for demand condition,
thus almost eliminating the A/F distribution issues.
The MPFI includes intake runner length adjustments, MAF
( Mass Air Flow) sensors, coupled to the ECM
( Electronic Control Module ).

7. The Longer intake runners are for Low Torque Demand in normal road
driving, amd Shrter Intake runner for Sudden High Rpms and
Acceleration requirements.
The MAF sensors are situated between the Air Filter and the Throttle
body in the Intake Manifold. This sensor accurately measures the Air
Flow Rates into the engine ( which is an indication of the engine rpm)
and sends the feedback to the ECM which inturn does the PROPER
FUEL METERING .
Thus a correct A/F ratio can be achieved in each cylinder. This inturn
assures
a better fuel Efficiency,
greater power output for same mixture ratio,
a much better control over the A/F ratio as per te instanteneous speed
demand.
Overall better performance.